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    <div>12121212</div>
    <hr style="width: 200px;" />
    <div>3333333</div>
    <p style="background-color: red;">This is<br > a paragraph</p>

    <p>This is <br>another </br>paragraph</p>
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注释  br用来换行 使用的是有 <br>  <br/>  </br> 但是浏览器都是解析成<br>
-->
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